Mdf

[Jerry Thompson]

What are the best screws to use with this material? Gluing is not an option. I'll be using it for a table saw sled. I could glue the front vertical piece but I need to screw the back to adjust it using the 5 cut method to get it aligned as close as I can.

[Ronald Blue]

You need to predrill and countersink as I understand. Here is a link to McFeely's and a MDF screw.
http://www.mcfeelys.com/product/0816-MDX/SPAX--8-x-1-34quot-Clear-Zinc-MDF-Screws

[Mike Heidrick]

I use coarse kreg screws in MDF without issue.

[Bobby O'Neal]

Any coarse wood screw I've used has worked for me.

[pat warner]

Indeed, put the head of the screw in the MDF and the threads in something else whenever possible.
(Rather than threading the MDF.)

[Jim O'Dell]

I've never used them, but hear that Confirmat screws are the screw for MDF. There is a corresponding drill bit for the screws. I've always used coarse deck screws and a countersink bit and have yet to have a failure. Just have to be careful you don't over torque them and strip out the wood. If you do, you'll have no holding power. Jim.

[David Dockstader]

Second the Confirmat recommendation. Put together a big, double-sided rolling bookcase for our woodworking club library with birch-faced MDF and Confirmat screws. The bookcase alone weighs about 400 lbs and it holds over 1000 lbs of books and magazines. We've had it rolling around for over a year and the screws (and glue) are holding wonderfully.